Intervals.icu eftp way too high

Could anyone explain how intervals.icu is getting my eFTP way over my best 10 minute power?

It looks to me kind of like it’s working out my ftp from my shorter efforts and then giving me a super low Time To Exhaustion

FWIW, I think could probably hold the eFTP for ten minutes (outdoors, uphill, fresh), but absolutely no chance I could hold it for anything approachig an hour

Screenshot 2021-07-31 at 09.04.34

Screenshot 2021-07-31 at 09.08.31

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It picks it based on a max effort somewhere between 3 - 12 minutes. I think you can adjust the duration somewhere, so you could exclude the 3min efforts, if that’s where you are particularly strong.

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Yes, in the settings you can change minimal efforts duration to estimate FTP. For example eFTP based on my 5 min power is 20W higher than my real FTP. Every estimation from short duration is not very usefull.

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Settings, Power settings, at the bottom of the section is estimated ftp min duration.

Mine is set on 480 - which from memory is 8 mins.

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The guys on this thread have it right. If your short power is good you need to set a longer min duration in /settings to get a good number. It will use the shorter efforts to estimate W’.

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Thanks all!

But why do they do that?

Just out of curiosity. I mean no one recommends a 3 minute ftp test.

critical power test is a 3-min all-out. But it is not an FTP test. My power curve looks more like a sprinter, and even though I’m not that anaerobically strong my intervals eFTP is too high at default setting.

My eFTP is pretty spot on from a 3min effort.

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Standardised power curves. With a large enough population you can predict an individuals threshold from the average curve. While we’re all unique in our own very special ways, we’re all still the same…

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Another question @davidtinker .

Since Feb I’ve used a PM on outside rides, the power tab data seems wrong.

For example garmin, TR shows 5s power as 1012w, but it only shows as 369w on intervals.icu.

Any idea’s on what I’m doing wrong?

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Additionally, I believe that if you have a bad power reading with a spike or two over three minutes, it could add a few watts to the 3 minute average and skew the calculation by a few watts. But the same spikes over 20 minutes have a negligible effect

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intervals does some clipping of data that is unexpected. Settings Power spikes is the one you want to fiddle with. I had to go through and fix a lot of mine when it came to doing sprint intervals the first time around. if you add the raw power chart to a ride you can compare and see where the clipping occurs.

Probably better to post questions like this in the intervals forum if you want a response from the man himself.

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Semi-thread-hijack…

Is there a way to set ftp for different time periods? I think it thinks my ftp from 2-3 years ago is the same as it is now, so my ctl/atl…etc are lower back then compared to what they probably should be.

I believe that you should be updating your FTP in your profile.

I am sure there is a better way, but if you look at your Activities page, set to “List” display, you can edit FTP for any entry.

There is probably a better way to address certain timeframes, but I don’t know.

Yes you can go a retrospectively set an FTP for a date. It will then use this ftp until a new one is set

I can’t immediately remember how I did it, but tapping on a day in the calendar you can set an eFTP

Look up ^^^
(I already gave instructions.)

Nah, I’m training to be in the danish pursuit squad

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If you msg me your Intervals.icu name I can have a look. But as others have suggested it is probably the power spike detection. By default power 30% above the model power curve for your FTP is clipped. If your FTP is set a bit low or you are really good at sprints then that might clip your 5s power. Rides that get clipped have a little orange bolt on the calendar. If the power is real then bump up the spike detection threshold for that ride or for all rides in /settings.

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